"They range from general abuse to visible Muslims on the street, to graffiti at mosques, through to a firebomb at a mosque.

"I guess in all of this scenario, the individuals who killed Lee said they wanted a war and we don't want to go down that route so we're asking for cool and calm heads."

Yvette Cooper, Shadow Home Secretary, added her voice to the calls for calm.

A number of arrests have been made since the Drummer Rigby's killing

"Anyone who seeks to divide our communities is doing the work of the extremists they say they oppose," she said.

"Mindless acts of violence against any of our communities serve no one. Some people are trying to use the vile attack in Woolwich as an excuse for more hatred, violence, and extremism. We must not let them."

Meanwhile, a 22-year-old man was due to appear before magistrates in Lincoln charged with making malicious comments on Facebook.

Benjamin Flatters, from the city, was arrested on Thursday after complaints were made to Lincolnshire Police about comments made on the social networking site which were allegedly of a racist or anti-religious nature.

A second man was visited by officers and warned about his activity on social media, a spokesman for the force added.

That came after two men were arrested and released on bail for making alleged offensive comments on Twitter about the murder.

A 23-year-old and a 22-year-old, both from Bristol, were held under the Public Order Act on suspicion of inciting racial or religious hatred.

Unemployed 28-year-old Adam Rogers, of Woolwich, has also been charged by police after allegedly posting an offensive message on Facebook.

And Michaela Turner, 23, of Southsea, has been charged with sending a "grossly offensive" message on Facebook - a post that has since been removed.

Surrey Police said a 19-year-old man had also been charged in connection with comments placed on a social media website following the murder of the soldier.

Mohammed Mazar, of Woking, has been charged with improper use of public electronic communications network under Section 127 of the Communications Act 2003.